Lucentis (Ranibizumab) in Diabetic Macular Oedema: a Treatment Evaluation

Adult patients with centre-involving diabetic macular oedema will be recruited to this single-centre study. Patients will undergo detailed baseline evaluation which will include:

• vision testing
• optical coherence tomography scanning
• fundus fluorescein angiography
• microperimetry
• colour contrast sensitivity testing
• electrophysiological testing

Patients will be randomised 2:1 to receive either ranibizumab intravitreal injection 4-weekly for 48 weeks or modified ETDRS macular laser therapy 12-weekly for 48 weeks.

Both groups of patients will return at 12, 24 and 48 weeks for repeat testing of the parameters evaluated at baseline.

Inclusion criteria

• Diagnosis of diabetes mellitus (type 1 or type 2)
• Retinal thickening due to diabetic macular oedema involving the centre of the macula and OCT central subfield ≥ 300 microns
• Best corrected visual acuity in the study eye between 55 and 79 ETDRS letters at 1 metre (Snellen equivalent ≥ 6/24 and ≤ 6/9)
• Media clarity, pupillary dilation, and subject cooperation sufficient for adequate fundus photographs
• Intraocular pressure less than 30 mmHg
• Ability to return for study visits
• Visual acuity in fellow eye ≥ 2/60
• Fellow eye has received no anti-VEGF treatment within the past 3 months and no expectation of such treatment in next 12 months
• No previous laser within 3 months of randomisation
• Ability to give informed consent throughout the duration of the study

Exclusion criteria

• Macular ischaemia
• Macular oedema from a cause other than diabetic macular oedema
• Co-existent ocular disease
• Presence of an ocular condition such that visual acuity would not improve from resolution of macular oedema
• Presence of an ocular condition that might affect macular oedema or alter visual acuity during the course of the study
• A substantial cataract that is likely to be decreasing visual acuity by 3 lines or more
• History of treatment for diabetic macular oedema at any time in the past 3 months
• History of panretinal scatter photocoagulation (PRP) within 3 months prior to randomisation
• Anticipated need for PRP in the 6 months following randomisation.
• Proliferative diabetic retinopathy in the study eye.
• A condition that, in the opinion of the investigator, would preclude participation in the study.
• Haemoglobin A1c > 11.0 %
• A past medical history of significant renal disease, defined as a history of chronic renal failure requiring dialysis or kidney transplant
• Blood pressure >170/100 mmHg
• Myocardial infarction, other cardiac event requiring hospitalisation, stroke, transient ischaemic attack, or treatment for acute congestive heart failure within 6 months prior to randomisation
• Major surgery within 28 days prior to randomisation or major surgery planned during the next 12 months at baseline
• Participation in an investigational trial within 30 days of randomisation that involved treatment with any drug that has not received regulatory approval at the time of study entry. Note: subjects cannot receive another investigational drug while participating in the study
• Systemic anti-VEGF or pro-VEGF treatment within 3 months prior to randomisation
• Pregnant or lactating women or women intending to become pregnant within the study period including 3 months after study cessation
• History of major ocular surgery (including cataract extraction, scleral buckle, any intraocular surgery) within prior 3 months or anticipated within the next 6 months following randomisation.
• Aphakia
• Uncontrolled glaucoma
• External ocular infection, including conjunctivitis, chalazion, or severe blepharitis
• Known allergy to fluorescein dye or to any component of the study drug
• Fertile male unwilling to use contraception for the duration of the study